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wwwduanemorriscom
19 October 2005
PITTSBURGH
NEWARK
VIA FEDEX
Division of Docket’s Management
Department of Health and Human Services
5630 Fishers Lane, Room 1061
Rockville, M D 20852
Re:
ALLENTOWN
WILMINGTON
HARRISBURG
PRINCETON
WZiTCHESTER
CITIZEN PETITION
Dear Sir/Madam:
The undersigned submits this petition in quadruplicate on behalf of a client under
21 CFR 10.30 or any other statutory provision for which authority has been delegated to
the Commissioner of Food and Drugs, including under 21 CFR 5.10, to request the
Commissioner of Food and Drugs to: i) re-evaluate the prescribing information/package
insert for new tramadol formulations in light of currently~avaiI&blesafety information a&
ii) designate extended release formulations of tramadol (Tramadol ER) as Schedule III
drugs under the Controlled SubstancesAct of 1970, as amended.
A.
Action Requested
The Petitioner requests that the Commissioner of Food and Drugs:
1.
Re-evaluate the prescribing information/package insert for new
tramadol formulations in light of currently available safety
information.
2.
Designate or recommend designation of extended release
formulations of tramadol (Tramadol ER) as Schedule III drugs
under the Controlled SubstancesAct of 1970, as amended.
and
B.
Statement of Grounds
(0
Overview
Several companies are developing extended release price-a-day formulations of
tramadol. The FDA has recently approved one formulation of Trarnadol ER; other
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formulations are expected to be approved over the next few years. These formulations
will undoubtedly be the subject extensive sales,marketing and physician sampling
efforts, particularly in view of the void created by the recent withdrawal of Vioxx@ and
Bextra@,and the genericization of Ultram@,Ultrace?, OxyContin@ and Duragesic*.
Tramadol ER carries all the documented adverse effects and abusepotential of
immediate release (I.R.) tramadol, combined with new safety considerations by way of its
extended release profile. The latter has come into particular focus due to the abuse of
OxyContin. Experience.with.OxyContin has shown that intentional crushing or
extraction of the active irgredient from the formulation by addicts and recreational drug
users destroys the controlled-release mechanism and results in a rapid surge of drug into
the bloodstream. Serious side-effects and death have been reported from such misuse. In
addition to the potential .for such effects with Tramadol ER, high concentrations of
tramadol, especially in combination with many popular antidepressants(which are
ubiquitous in the setting:of chronic pain) can produce serotonin syr&-ome. If not
properly diagnosed and treated, serotonin syndrome can lead to life-threatening
complications and death.
Tramadol is a synthetic, centrally acting analgesic which exerts its analgesic
effects by inhibiting reuptake of norepinephrine and serotonin and by activation of popioid receptors. Tramadol binds to the p-opioid receptor, although its principal active
(Ml) metabolite, mono-0-demethyi-tramadol is up to 6 times more potent in producing
analgesia and 200 times more potent in p-opioid binding @Jltram Package Insert),
In the United States,tramadol is presently available as an oral I.R. single-entity
tablet (Ultram, others) and as a fixed-dose combination with acetminophen (Ultracet@,
others). The approved indication for single-entity oral tramadol is “for the management
of moderate to moderately severepain.” The approved indication for Uitracet is for the
“short-term (five days or less) managementof acute pain”. It should be noted that due to
the genericization of Ultram, there has been not been any significant physician sampling
or promotion of I.R. tramadol for several years, This will change with the introduction
branded Tramadol ER formulations from various companies. Recently, FDA has
approved a new Tramadol ER formulation from Biovail Laboratories in strengths of 100,
200 and 300 mg tablets,for the indication of “moderate to moderately severe chronic pain
in adults who require around-the-clock treatment of their pain for an extended period of
time.” This product is not yet marketed.
Receptor bindirig and pharmacologic evaluations in a variety of non-clinical
models of opioid abuse and dependenceprovide compelling evidence that tramadol and
its Ml metabolite bind’to the opioid receptor, substitute for morphine and attenuate or
suppressesmorphine abstinence.
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Data from FDA, :the Drug Enforcement Administration &@A), the Drug Abuse
Warning Network (DAWN); the American Association of Poison Control Centers Toxic
Exposure Surveillance system (T&B), National Survey on Drug Use and Health
(NSDUH) and other credible sources indicate that tramadol iswidely abused.
Surprisingly, the innovator fun~ed~surveillancestudies for I.R. tramadol are “outliers” in
suggesting minimal risk, of abuse and drug addiction (Cicero et al, 1999; Knisely et al,
2000;).
(ii)
Nonclinical Ph4mnacology Indicates Classic Qpioid and
SerotooninEffects
Tramadol avidly binds to the p-receptor. Its principal active metabolite, mono-Odemethyl-tramadol (Ml) is up to 6 times more potent than the’parent @rugin producing
analgesia and 200 times more potent in p-opioid binding.(Desmeules et al., 1996;
Hennies et al., 1988; Raffa et al., 199%).
The analgesic effect of tramadol in the tail flick test in rats and mice are partially
antagonized by naloxone (Carlsson & Jurna, 1987; Kayser et al., l991; Raffa et al.,
1992). Pretreatment wi;th tramadol in mice and r&s resul-tsin withdrawal symptoms
induced by opioi$ antagonist challenge,including. the Straub tail phenomena,
withdrawal jumping and loss of bodyweight (Friderichs et .al. 1978; Murano et al.
1978; Nickel & Aledter 1987). Similarly, administration of naloxone to monkeys who
receiving 8 weeks of treatment with progressivelyincreasing- osmzof tramadol up to
100 mg/kg daily results in classic signs of opioid withdrawal (Yanag&a 1978). In
continuous self-administration-experiments with naive and conditiuned monkeys,
tramadol has a reinforcing effect (Y&agita 1978).
Replacement oftramadol with the opioid antagonists ~v~lo~h~ and naloxone
precipitate weight loss m rats and characteristic signs of opioid withdrawal in mice and
rats (Friederichs et al., 1978, Murano et al., 1978; Wakasa et al., 1994).
Trarnadol fully &bstitutes, for .morphine at high dosesin, a rat model of
dependenceand this e&ect is antagonizedby the opioid antagonist, naltrexone (Ren and
Zheng, 2000). Other studies have suggestedthat tramadol only partially substitutes for
morphine in animal models. An important consideration is the selection of tramadol dose
and the role its principal active metabolite (Ml), which accumul&teswith repeated dosing
and would undoubtedly be a C-II scheduled drug if it were ~o~er~i~li~ed in the USA.
(iii)
kpidemiologiq Data Demonstrate Ab@sean
P&e&al
According to the Drug Enfor,mment Administration, ‘“rramadol is abused for its
opiate effects. The current pattern oftiamadol abuse in the US involves street drug
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addicts, chronic pain patients, and health professionals. As an uncontrolled substance,
there are no Controlled SubstanceAct regulations regarding ~~ufa~~~g,
distribution,
or prescription of this medication.” (b~:llwww.de~versi~~.~do~
concern/tramadol..htm.).:DEA &es the Drug Abuse ‘Warning Networ~(DAWN) data for
drug related hospital emergency roomepisodes. In 2002, there were I.,714 episodes for
tramadol and a total of 7,890 episodes from. 1998 through 2002. DAWN medical
examiners reported that tramadol was involved in 95 drug-related deaths in 2002 and a
total of 382 deaths from, 1998 tbrou& 2002.
According to the;2002 National Survey on Drug Use and Health (NSDUH),
approximately one million individualshave taken tramadol (Ultram) fornon-medical use.
This is approximately the same’incidence of non-medical use reported,..forDilaudid@ and
approximately 50% of the incidence reported for OxyContin. Among non-medical
OxyContin users, 18.3% also reportedconsuming Ultram for non-medical reasons.
In the two most recenttannual mports of the American Association of Poison
Control Centers Surveillance System (TESS), tramadol ranked only second to oxycodone
in the number of opioid,exposure cases (Watson et al, 2002).
A study published in the September 2004 issue of the .Iournal of Forensic
Sciences of 66 deaths in which ,short-acting tramadol was de&ted in the decedent’s
blood notes that “ . . tramado may be a significant contributor to lethagintoxication when
taken in excess with other drugs . . .“. The’study discussest&role of opioid and
serotonin effects in such deaths (Clarkson et al, 2044)
According to a recent report in JAMA regarding drugs abused.by physicians,
tramadol was the third most frequently mentioned abusedopioid. It was more frequently
mentioned than was fentanyl, oxycodone or hydromorphone (Skipper et al, 2004; Skipper
et al, 2005; Adams et al., 2005).
The FDA’s Me&watch systemhas received appro~~a~~l~ a 1900 domestic
adverse-eventreports for tramadol coded as “drug dependence”,“drug withdrawal” or
“drug abuse”(Brinker et al, 2002).
There are also numerous reports in the literature of drug abuse, addiction.,
physical dependence,seizures and withdrawal on abrupt cessation with ,&amadol
(Barsotti et al, 2003; Bjinker A et al, 2-002;Ehrem-eichand Poser, 1993; Freye and Levy,
2000; Leo et al, 2000; Liu et al, 1999; Marquardt et al, 2005; Reevesand Liberto, 2001;
Ripamonti et al, 2004; Rodriguez~Willamanan,et al 2OOQ;Prescrire Int. 2003; Prescrire
Int. 2005; Scherbaum et al, 2005; Se+.y et al, 2003; Thomas and Sure&h,2000; Soyka et
al, 2004; Yates et al, 2601; Zacny, 2005)
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Tramadol has also been found to be effective in substituting for or treating
moderate heroin withdrawal, with efficacy comparabfe to buprenorphme.and superior to
clonidine (Tamaskar et al, 2003; Sobey et al, 2003).
(iv)
Extended-Release F6nnulatians way Present: New Safety
Consideratign
Tramadol’s pain irelieving effects are due to serotuninad norepinephrine
reuptake inhibition, and 8througfian opioid effect. Tramadol is an uns&eduled narcotic,
therefore it is readily available like any.ordinary prescription drug.
Commercially available I.R. tramadol (Ultram) releases5@mgof tramadol per
tablet into the systemic circulation Qver-severalhours. New, extended release
formulations are designed to gradually releasetheir much 1,arger.trsm&oI content over a
24-hour period, Consequently,,prior,postniarketing surveillance.fi-urn f.R may not fully
predict the abuse potential of the new Tramado ER formulations. Experience with
OxyContin would suggest that if formulations of Tramadol ER are tampered, the entire
24-hour drug supply may be released mto the bloodstream, with result& potential for
toxic effects.
Most recreational drug users and addicts have a unit of use wmch is one tablet or
capsule. The 24-hour supply oftramadol contained in one t&let, instead of 4 to 6 tablets
means that there is a risk that such formulations may be highly sought<by drug. addicts
and recreational drug users alike for non-medical use. Interitional tampering from
Tramadol ER formulations has.the potential to rapidly deliver a massive dose .snd
produce neurological toxicity, including agitation, Seizures,corria and respiratory failure
from both from opioid and serotonergic mechanisms.
During its non-medical use by drug.addicts md recreational users, Tramadol ER
is likely to be crushed to provide maximum opioid effects. Since tramadol produces dose
dependent seizures a&dose dependentserotonin syndrome, there is me potential for a
compounded risk. The:occurrence of serotonin syndrome has been well documented with
tramadol given alone, with serious asldpotentially fatal consequences-(c%rksonet al,
2004; Garrett, 2004; Kitson and Carr; 2005). The sudden exposure ofpatients to large
concentrations of tramiidol from crushed solid dosage forms df Tramgdol ER, especially
in the face of ubiquitouis use ofSSRI”s and SNRI’s m chro~c pain may have important
medical consequences.;(Clarkson et al, 2004; Gonzizfez-Pintoet al, .2001; Houlihan,
2004; Egberts et al, 1997; Kesavanand SobaIa, 1999; Ltige-Assehe~feldt, 2002;
Mahlberg et al, 2004; Mitt& et al, 2004). These are additional reasons to require C-III
scheduling for Tramadol ER.
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69
Skhedule for Tnfmaaloi
It is widely knovvn in the pharmaceutical industry and ~o~gst,~~ci~s
that
Schedule II status results in maximal prescribing restraint and t!&t only Sghedule II and
Schedule III have “teeth:‘. The Petitioner recommends ‘th& FIJA seriously consider a
minimum Schedule III status for Tramadol. Any less stringent a controlled substance
schedule is widely considered to be inadequate. The recent decision of the FDA and
DEA to reschedule buprenorphine from C-V to C-III is consistent with the Petitioners
request. In addition, abuse liability issues are often regional or national in nature;
evidence would suggest that the magnitude of diversion and abuse’ofQxyContin was
particularly high in the @sited-States. Consequently, scheduling decisions need to reflect
the potential risk in the eontext of the American environment.
(vi)
Comprehensive Safety AssessqeJa-tand Label Review Needed
Tramadol I.R. formulations have a role in the tre$meMqf acute and chronic pain,
and Tramadol ER formulations, have utility in the tr.e@mentof,&ronic~ pain; they provide
clinicians with an alternative treatment option for patients unresponsive to other drugs.
Since the commerciali&ion of Ultratrr approKimately 10 years ago, the therapeutic
landscapehas changed significantly~ There is widespread ‘use of non-TCA
antidepressantsto treat b wide variety &affective disorders, including co-morbid
depression in patients with chronic pain and as adjuvant analgesics (“off-label”).
Although the concurrent use of SSRI’s, SNRI’s and TCA’s and tramadol is
contrainidicated, there continues to be widespread concomitant use. New evidence
suggeststhat there is a risk of serotonin excessfkom such con&rrent use, resulting in
serotonin syndrome. Further, with the use of Tramadol ER, intentional crushing of the
formulation may result in a dose dependentincrease in. the risk of seratonin syndrome,
overdose and seizures. iThesepotetitial risks, which may be uniquetoTramado1 Eli, need
careful evaluation in the context of a&available safety inform&ion. The risk may not
have been fully evaluated in clinical trials of Tramadol ER due to the exclusion of study
subjects taking corrcurrent SSRI’s, SNRI’s and TCA’s.
(vii)
+egitimate R& for Upioids: Aeh!eving 811k
Appropriate
Balance
.
The Petitioner believes that recent experience with opisid drug diversion and drug
abuse, and associatedpublic health implications warrant prudent regulatory practices,
notwithstanding any commercial imphcat@ns to pharmaceut+al companies. A C-III
status for tramadol means thatclinicians will think very carefully about the risk benefit
profile of the drug in the specific p@ent, every time they -3vritea pre%Xiption for
tramadol ER. A C-III schedule provides an appropriate balance between the rights of
patient’s with pain to accessTramadol’ER, while safeguarding pub& safety.
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The Petitioner believes that this may be the final regulatory opportunity to
meaningtilly evaluate the safety of Tr$madol ER, both in tern% of the;adequacyof the
prescribing information and the scheduling of Tramadol ER &~;aC-IIT drug, particularly
in light of lessons learned from our experience with oxycodone ER (OxyContin) and
other analgesics.
C.
Enviroamexbkl Xmkkct
The action requestedby the Petitioner is exempt from the requirements for an
Environmental impact Statement or an Environmental Assessment,under~21 CFR 25.3 1.
D.
Economic Impact
The Petitioner does not believe that an economic impa& statement is-applicable,
but will agree to provide such an anz$ysisif reqnestedbythe Commksioner in
accordancewith 21 CFR 10.30(b).
The undersigned certifies that to the best knowledge ofthe ~~~~~~,
this
petition includes all information and views on which the petition relies, and that it
includes representative data and infurmation known to the petitioner* which are
unfavorable to the petition.
Attachment: References
Copy to (letter onlv):
Dr. Bob Rappaport, Division of Anesthesia, Analgesia. & Rheumatology Products, FDA
Dr. Deborah Leiderma& Dire&or, Controlled SubstanceStaff, FDA
PH1\1500197.1
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